U.S. patent number 4,990,339 [Application Number 07/124,257] was granted by the patent office on 1991-02-05 for dermal treatment film.
This patent grant is currently assigned to H. B. Fuller Company. Invention is credited to William L. Bunnelle, Steven L. Scholl, Eugene R. Simmons.
United States Patent |
4,990,339 |
Scholl , et al. |
February 5, 1991 |
**Please see images for:
( Certificate of Correction ) ** |
Dermal treatment film
Abstract
A water soluble dermal treatment film for dressing burns,
surface wounds, cuts, scrapes, rashes or other dermal wound or
lesion comprises a flexible sheet-like dressing made of
polyalkyloxazoline. The dressing can have a structural layer and a
pressure sensitive adhesive layer. The structural layer can be made
of a polyalkyloxazoline composition formulated to obtain a flexible
structural sheet. The pressure sensitive adhesive layer can be
formulated to obtain pressure sensitive properties, maintaining the
treatment film in position during its use. At such time the
treatment film is to be removed, it can be removed without harsh
scrubbing methods with a warm aqueous spray or soak. The sheet-like
treatment means can be reinforced or impregnated with medicinal
compositions to induce healing, reduce infection or stabilize the
skin surface.
Inventors: |
Scholl; Steven L. (Cottage
Grove, MN), Simmons; Eugene R. (Maplewood, MN), Bunnelle;
William L. (Hugo, MN) |
Assignee: |
H. B. Fuller Company (St. Paul,
MN)
|
Family
ID: |
22413770 |
Appl.
No.: |
07/124,257 |
Filed: |
November 16, 1987 |
Current U.S.
Class: |
424/443;
128/113.1; 128/114.1; 424/447; 424/448; 523/105; 523/111; 524/27;
602/53 |
Current CPC
Class: |
A61K
9/7053 (20130101); A61K 9/7061 (20130101); A61L
15/26 (20130101); A61L 15/585 (20130101); A61L
15/26 (20130101); C08L 79/00 (20130101); A61L
15/585 (20130101); C08L 79/00 (20130101); A61F
13/00063 (20130101); A61F 13/0206 (20130101); A61F
13/0226 (20130101); A61F 13/0253 (20130101); A61F
13/0269 (20130101); A61F 2013/00519 (20130101); A61F
2013/00625 (20130101); A61F 2013/00634 (20130101); A61F
2013/00642 (20130101); A61F 2013/00655 (20130101); A61F
2013/0091 (20130101); A61F 2013/00931 (20130101) |
Current International
Class: |
A61F
13/02 (20060101); A61L 15/26 (20060101); A61K
9/70 (20060101); A61L 15/58 (20060101); A61L
15/16 (20060101); A61F 13/00 (20060101); A61L
015/24 (); A61K 007/40 (); A61F 013/00 () |
Field of
Search: |
;536/20 ;424/443,447,448
;523/105,111 ;128/113.1,114.1,156 ;524/27,612 ;106/162 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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|
|
|
|
|
1179913 |
|
Dec 1874 |
|
CA |
|
1180622 |
|
Jan 1985 |
|
CA |
|
0138385 |
|
0000 |
|
EP |
|
Primary Examiner: Griffin; Ronald W.
Attorney, Agent or Firm: Merchant, Gould, Smith, Edell,
Welter & Schmidt
Claims
We claim:
1. An aqueous soluble dermal treatment film which comprises:
(a) a structural layer comprising a polyalkyloxazoline polymer;
and
(b) a pressure sensitive adhesive layer comprising 10-75 wt. % of a
polyalkyloxazoline polymer, 10-75 wt. % of a functional diluent
comprising a hydroxy compound or a carboxylic acid compound; and
5-35 wt. % of a compatible tackifier.
2. The film of claim 1 wherein the polyalkyloxazoline polymer is a
compound of the formula: ##STR4## wherein R is a C.sub.1-12 alkyl
and n is about 50 to 100.000.
3. The film of claim 1 wherein the structural layer or the pressure
sensitive adhesive layer additionally comprises an acrylic acid
polymer.
4. The film of claim 3 wherein the acrylic acid polymer comprises
an ethylene acrylic acid copolymer.
5. The film of claim 1 wherein the tackifier comprises a
composition selected form the group consisting of a hydrogenated
wood rosin, terpene-phenol resin and mixtures thereof.
6. The film of claim 1 wherein the pressure sensitive adhesive
layer comprises 10-50 wt. % of a polyalkyloxazoline polymer, 10-30
wt. % of a hydroxy wax, and 15-35 wt. % of a tackifying agent.
7. The film of claim 1 wherein either the structural layer, the
pressure sensitive adhesive layer or both additional comprise an
antimicrobial composition.
8. The film of claim 1 wherein the structural layer additionally
contains a fiber.
9. The film of claim 1 wherein additionally comprises a wound
healing promoter.
10. The treatment film of claim 9 wherein the wound healing
promoter comprises chitin, chitosan, derivatives thereof or
mixtures thereof.
11. An aqueous soluble dermal treatment film which comprises:
(a) a structural layer comprising a polyalkyloxazoline polymer;
and
(b) said layer containing a component selected from the group
consisting of a fiber reinforcement, an antimicrobial, an
analgesic, a wound healing promoter, or mixtures thereof.
12. The film of claim 11 wherein the polyalkyloxazoline polymer is
a compound of the formula: ##STR5## wherein R is a C.sub.1-12 alkyl
and n is about 50 to 100.000.
13. The film of claim 11 wherein the structural layer additionally
comprises an acid functional compound, a hydroxy functional
compound, or mixtures thereof.
14. The film of claim 11 wherein the film additionally comprises a
tackifier.
15. The film of claim 11 wherein the treatment film additionally
comprises a woven or nonwoven fabric.
16. The film of claim 11 wherein the treatment film additionally
comprises a wound healing promoter.
17. The film of claim 16 wherein the wound healing promoter
comprises chitin, chitosan, derivatives thereof, or mixtures
thereof.
18. The film of claim 11 which comprises a pressure sensitive
adhesive film.
19. The film of claim 11 which comprises a non-tacky film.
20. An aqueous liquid concentrate for application to the surface of
skin to form a dermal treatment film removable by an aqueous
treatment, which concentrate comprises:
(a) a major proportion of an aqueous liquid;
(b) about 5 to 85 wt. % of a polyoxazoline polymer to form a
structural layer; and
(c) an effective amount of a compatible tackifier, plasticizer or
mixtures thereof.
21. The aqueous concentrate of claim 20 wherein the
polyalkyloxazoline polymer is a compound of the formula: ##STR6##
wherein R is a C.sub.1-12 alkyl and n is about 50 to 100.000.
22. The aqueous concentrate of claim 20 wherein the tackifier
comprises a composition selected from the group consisting of a
hydrogenated wood rosin and a terpene-phenol resin.
23. The aqueous concentrate of claim 20 wherein the plasticizer
comprises a composition selected from the group of castor oil,
hydroxylated fatty acids or mixtures thereof.
24. The aqueous concentrate of claim 20 wherein the composition
comprises about 10 to 75 wt. % of a polyalkyloxazoline polymer.
25. The aqueous concentrate of claim 20 wherein the composition
additionally comprises an antimicrobial, an analgesic, a wound
healing promoter, or mixtures thereof.
26. A method of treating a dermal lesion which comprises applying
to the dermal surface an aqueous concentrate capable of forming a
treatment film removable by an aqueous treatment which
comprises:
(a) a major proportion of an aqueous liquid; and
(b) an effective concentration of a polyalkyloxazoline polymer to
form a structural layer.
27. The method of claim 26 which additionally comprises applying
the aqueous concentrate to a fiber applied to the dermal
surface.
28. The method of claim 26 wherein the concentrate additionally
comprises a compatible tackifier, a plasticizer or mixtures
thereof.
29. The method of claim 26 wherein the polyalkyloxazoline polymer
is a compound of the formula: ##STR7## wherein R is a C.sub.1-12
alkyl and n is about 50 to 100.000.
30. The method of claim 26 wherein the composition comprises about
10 to 75 wt. % of a polyalkyloxazoline polymer.
31. The method of claim 26 wherein the concentrate additionally
comprises an antimicrobial, an analgesic, a wound healing promoter,
or mixtures thereof.
Description
FIELD OF THE INVENTION
The invention relates to a polymeric material in a film or
sheet-like format that can be applied to a mammalian or human
surface as a dressing. Preferably, the sheet-like material can be
applied to human skin in various formats for treatment of disease,
rashes, wounds, lesions or other dermal malady.
BACKGROUND OF THE INVENTION
A great deal of attention has been directed to developing
sheet-like dressings, for the treatment of body surfaces, using a
variety of materials. Curtis et al, U.S. Pat. No. 2,579,367 teaches
using a coagulated proteinaceous solution or paste, and forming a
soluble, semi-permeable, artificial bandage. Anderson, U.S. Pat.
No. 3,328,259 teaches a film prepared from a cellulose derivative
such as sodium carboxymethyl cellulose, glycerol, and water. The
cellulose derivative is described as a composition that will cause
the coagulation of blood plasma. Catania et al, U.S. Pat. No.
3,969,498 teaches a flexible wound dressing formed primarily from a
water soluble dextran polymer. Mason, Jr. et al, U.S. Pat. Nos.
4,391,799 and 4,393,048 teach a protective gel composition for
treating white phosphorous burn wounds containing water soluble
hydrogels of alkali metal alginate and glycerine. Murray, Canadian
Pat. No. 1,180,622 teaches forming a laminate comprising two sheets
of a water soluble material having a layer of a mendicament.
In the treatment of dermal lesions, significant problems can arise
in contacting lesions with treatments in general and with
sheet-like dressings in particular. The application of a dressing
can often disturb injured tissues. Portions of dressings can often
be included in the formation of new skin during the healing of
abrasions, cuts, and other skin injury. The removal of many
dressings can cause significant pain and often can re-open at least
portions of partially healed wounds. More particularly, in the
treatment of other wounds such as burns and other more serious
injuries or surface lesions that involve a significant area of the
skin, simply applying many available sheet-like dressings to the
wound can cause severe pain and discomfort. Further, the removal of
such dressings after a period of a few days can cause additional
pain and suffering. Further, sheet-like dressings need to be
formulated such that the dressings can include antibiotic
compositions, compositions that can promote wound healing, pain
killers, and other treatment agents.
Accordingly, a substantial need exists for dressings that can be
applied and removed from the skin surface with minimal pain and
discomfort while at the same time providing a vehicle for the
application of beneficial treatments to the skin surface.
BRIEF DISCUSSION OF THE INVENTION
The invention resides in a dermal treatment film that can be easily
applied in a sheet-like form or cast-in-place form, a cooled
extruded hot melt or a liquid concentrate and can be easily removed
with an aqueous agent including cool water, warm water, a detergent
containing aqueous solution, and other mild aqueous cleaning or
treatment agents.
The dermal treatment film can be formed into a structurally stable
sheet-like material. In a preferred format, the dressing can have a
pressure sensitive adhesive (PSA) layer in conjunction with a
structural layer. The structural layer can comprise a non-tacky
layer. The pressure sensitive adhesive layer can comprise 10-75 wt.
% of a polyalkyloxazoline polymer, 10-75wt. % of a functional
diluent comprising a hydroxy compound or a carboxylic acid
compound, and 5-50 wt. % of a tackifier compatible with the
pressure sensitive adhesive formulation.
The nontacky layer can comprise a natural or synthetic fiber,
fabric or tape adhered to the wound and skin surface using the
adhesive of the invention. Commonly available fibers, fabrics and
tapes can be used in this aspect of the invention including woven
and nonwoven fabrics made from cotton, rayon, synthetic polymers,
tapes made from polymer and cellulosic films, nonwoven fibers made
from fiberglass, cotton, polypropylene, and other sources. The
structural layer can also comprise a nontacky layer prepared from
the polyalkyloxazoline polymer of the invention.
The polyalkyloxazoline structural layer can contain a broad array
additional ingredients that can aid in adhesion to the skin
surface, can enhance the structural stability of the film, or can
promote wound treatment or skin stability including agents such as
antibiotics, antiseptics, analgesics, fibers, a woven or nonwoven
mesh, dyes, solvents, curing agents, or other functional
compounds.
The dermal treatment in the form of a film extruded from a hot
melt, can have a release liner covering a PSA (pressure sensitive
adhesive) layer, and can be applied to the skin by removing the
release liner and applying the dermal treatment PSA layer to a
wound or other lesion on the skin. Alternatively, the dermal
treatment can be formed by casting the pressure sensitive adhesive
layer and the polyalkyloxazoline structural layer in situ on a
wound site or from an aqueous or other solvent based system of the
composition. The materials can be sprayed on, brushed on or coated
in an immersion step.
At such time as the dressing needs to be replaced or removed, the
treatment film can be completely dissolved in an aqueous bath and
removed from the wound site in the absence of any mechanical
contact. Alternatively, if the sensitivity of the wound and the
surrounding skin is minimal, the removal of the film can be aided
using mild scrubbing action with warm water or aqueous
cleaners.
DETAILED DISCUSSION OF THE INVENTION
The dermal treatment film of this invention is a sheet-like
polymeric material that can be applied to the skin in a variety of
formats for the purpose of treating the skin surface. The polymeric
materials that make up the dermal film comprise conventional
material and synthetic fiber fabrics and films in conjunction with
polyalkyloxazoline polymer which can aid in maintaining structural
integrity, bond strength to the skin, or aid in the treatment of
the skin surface.
The sheet-like dermal treatment film of the invention can contain
antimicrobial agents that can be dissolved or suspended in the
polymer material or blend thereof. Antimicrobial agents when
included in the film treatment means of the invention are typically
mixed into a hot melt or in an aqueous solution that can contain a
thickener if required which is then added to the polymer base
during the manufacture of the sheet-like treatment layers.
Antimicrobial agents that can be used in the invention are well
known dermal treatment agents including, for example, sulfadiazine,
silver sulfadiazine, benzalkonium chloride, cetalkonium chloride,
methylbenzethonium, neomycin sulfate, hexachlorophene, eosin,
penicillin G, cephalothin, cephaloridine, tetracycline, linkomycin,
nystatin, kanamycin, penicillinase-resistant penicillins,
fradiomycin sulfate, and other well known antimicrobial agents. If
the antimicrobial agent is not sufficiently water soluble, the
antimicrobial can be introduced into the polymer material of the
invention by adding the antimicrobial in a powder form or carried
on a powder support. The antimicrobial, which can be diluted by
carriers, can be added to the surface of the sheet-like material
during formation, to the polymer blend or can be added in
combination with other film components.
The amount of antimicrobial agent added to the treatment material
should be sufficient to provide an effective antimicrobial
concentration or dose rate of the material to the skin surface.
Typical concentrations of standard antimicrobials range from about
0.01 to 5% by weight of the antimicrobial in the film
treatment.
For structural and wound treatment purposes, the film treatment of
the material can contain either natural or synthetic fibers. The
fibers can be woven or nonwoven and can be randomly or uniformly
distributed throughout the polymer material. The fibers can be of
minimal length, about 1 millimeter or greater, or can, in a woven
or nonwoven fabric format, have a length equal to or greater than
the dimensions of the polymeric film material of the invention.
Fibers that can be included in the film treatment of the invention
include rayon, nylon, cellulose acetate, modified proteins,
polyesters, polyacrylics, polyethylene, polypropylene, glass
fibers, polyvinyl alcohol polymers, and others. Natural fibers that
can be used include fibers from both animal or plant sources.
Examples of natural plant fibers include cotton, flax, hemp, jute,
linen and other well known fibers.
A preferred ingredient for the films of the invention comprises
chitin. Chitin is a naturally occurring aminopolysaccharide
occurring as a structural material, internal or external skeleton
in the shells of mollusks such as squid, lobsters, crabs and other
marine invertebrates Chitin can be obtained from the structural
body members of these organisms in relatively pure form and can be
made into a powder, a fiber, a sheet, or other functional form.
Chitin has the unique ability to promote healing of surface
lesions. Accordingly, chitin can be incorporated into the treatment
films of this invention as a powdered or granular filler, randomly
distributed fiber, a woven or nonwoven fabric, or as a film
support.
During manufacture such fibers can be incorporated into the
sheet-like materials of the invention in a variety of formats. The
fibers can be in the form of a woven fabric, a nonwoven fabric or
can be randomly distributed throughout the treating material.
During manufacture the fibers can be incorporated by casting the
polymeric materials onto or around a woven or nonwoven fabric from
a solvent source, extruding the fabric with the polymeric material,
spraying the polymeric material onto the fabric, or other well
known conventional manufacturing techniques. Additionally, random
fibers can be added to the material during manufacture, can be
blended and can be extruded as a component of the polymeric
material.
Virtually any skin problem requiring treatment by an active
surfactant or protection from the effect of sunlight, dirt, water
or other environmental hazard, can be treated using the dermal film
treatment of the invention. Such problems include dermatitis,
puncture wounds, abrasions, cuts, eczema, pimples, blackheads,
poison oak and poison ivy contact dermatitis, etc. Wounds referred
to in the invention are open wounds caused by the injury of living
tissues through a mechanical insult or through surgical operation.
An incision caused by scalpel or a knife, stab wound, needle market
or pocket knife wound or crushing wounds such as stretching,
elongation, etc. can be treated. Additionally, burns caused by
fire, chemical hazard, electric shock, radiation (X-ray, gamma ray,
microwave or other photon-based energy, beta (e.sup.-) particle,
alpha particle, proton, or other ionizing radiation) or other
energy source can be treated using the compositions of the
invention. Skin infections including infected wounds, skin
abscesses, boils, leprosy, etc. can also be treated.
The sheet-like treatments of the invention can be produced in a
variety of formats. The size of the film can vary from small (an
area of about 0.5 to 1 cm.sup.2) that can be applied to small
puncture wounds or other dermal problem). Alternatively, the
sheet-like substrate can be long, thin sheets of material that can
be used to wrap fingers, arms, legs, torso, or head wounds with a
single or multiple layer of the material having an area of about 1
cm.sup.2 to m.sup.2. Alternatively, the material can come in the
form of large (about 1 to 10 m.sup.2 or more) sheets that can be
applied to larger skin surface areas such as torso, upper thigh,
gluteal region, or can be cut into smaller shapes for the purpose
of treating irregular shaped burns, abrasions, chemical burns, or
other lesions.
The treatment films of the invention can vary in thickness
depending on the number of layers and the compositions used in
forming the treatment film. A single layer non-adhesive film can be
from 0.01 to 1 millimeters, preferably 0.02-0.5 millimeters, in
thickness in order to provide minimal structural integrity.
Bi-layer structural treatment films having a structural layer and a
pressure sensitive adhesive layer with release liner can range from
about 0.02 to 3 millimeters, preferably 0.03 to 2 millimeters, in
thickness. Additional layers can add similar increments to the
thickness dimension of the film.
Such sheet-like treatment films can be formed from a single layer
of the polyethyloxazoline polymer that can include other
ingredients. Alternatively, the polyethyloxazoline polymer sheet
can have a coating of a pressure sensitive adhesive composition.
The pressure sensitive adhesive layer can be formed by introducing
into the polyethyloxazoline polymer sufficient tackifier and other
ingredients to create a pressure sensitive adhesive layer in the
film treatment itself. Alternatively, the structural layer can be
coextruded or cast in conjunction with a tackified
polyethyloxazoline layer which adheres and can be applied to dermal
wounds.
The pressure sensitive adhesive layer on the treatment film can be
covered with a release liner that protects the adhesive nature or
tackiness of the adhesive layer until the release liner is removed
just prior to adhesion to the dermal surface.
As currently envisioned, the treatment film of the invention can be
manufactured and applied to a treatment site in one of two
preferred modes. First, the treatment film can be formed using hot
melt extrusion technology, packaged, distributed and sold as an
adherent treatment. Secondly, the treatment film can be formed in
situ on a sensitive dermal lesion by applying the material in a
liquid form which will solidify over time.
The polymeric polyalkyloxazoline polymer compositions of this
invention are typically manufactured by heating in an appropriate
formulation vessel the tackifier or plasticizer portion of the
invention in conjunction with the optional inorganic filler or
other diluent portion. Such components are heated in a stainless
steel vessel until melted and into the melt is added under
conditions of high shear the polyalkyloxazoline polymer. The
polymer should be added to the melt at a rate such that it is
readily and smoothly incorporated into the melt mixture. After the
polymer has been added, additional materials including other
polymeric materials, antimicrobials, fibers, etc. can be added
under appropriate conditions.
The following Table contains a formulation for the preferred
composition of the treatment film of the invention having a
structural layer and a pressure sensitive adhesive layer.
TABLE 1 ______________________________________ Preferred Polymeric
Constituents Structural Layer PSA Layer Useful Preferred Useful
Preferred ______________________________________ PeOx 5-85 10-50
5-75 10-40 Tackifier 0-30 0-25 1-35 2-30 Plasticizer 5-60 20-50
5-60 10-50 Fiber 0-60 1-50 0-60 1-50 Antimicrobial 0-10 0.01-5 0-10
0.01-5 Thermoplastic 0-25 0.1-25 0-25 0.1-25 polymer
______________________________________
The polyalkyleneimines (polyalkyloxazolines) which can be used in
the adhesives of this invention are commonly prepared by the
polymerization of heterocyclic monomers of the general formula I:
##STR1## wherein A is a C.sub.1-15 alkyl and n is 100-10,000. The
polymers and polymerization techniques are in general as disclosed
in U.S. Pat. Nos. 3,483,151 and 3,293,245, the disclosures of which
are incorporated by reference herein.
Preferred polyalkyleneimines (polyalkyloxazolines) include
N-substituted polyethyleneimines and polypropyleneimines which are
prepared by polymerizing heterocyclic monomers of the formula I
wherein n is 2 or 3. These polyalkyleneimines can be represented by
the general formula II: ##STR2## wherein A is as defined
hereinabove, n is about 2-3 and m is about 50-100,000, preferably
100-7,500.
The molecular weights of the polymers derived from such monomers
can range from less than 50,000 to 500,000 or above. The polymers
are available in low (less than about 100,000), moderate (about
100,000 to 300,000) and high (greater than about 300,000) molecular
weights. These polymers are soluble in water and many polar organic
solvents, but can be advantageously insoluble in non-polar organic
solvents. The polymers are thermally stable, low in solution
viscosity, possess acceptable melt flow properties, and have
acceptable human toxicity. The substituted polyalkyleneimine
(polyoxazoline) polymers of this invention are available from the
Dow Chemical Company.
The most preferred polyoxazoline polymers of this invention, for
reasons of their low cost and high performance in adhesive
applications, are polymers having the formula: ##STR3## wherein m
is as defined above and R is a C.sub.1 -C.sub.12 alkyl such as
methyl, ethyl, iso-propyl, t-butyl, cyclohexyl, cyclopentyl,
methyl-cyclohexyl, dodecyl, and the like. Preferably, R will be an
alkyl group having about 1-5 carbon atoms.
The polymer sheet-like compositions of this invention can contain a
carboxylic acid functional compound having an acid number of at
least 75. Both monomeric and polymeric acid functional compounds
can be used to enhance a number of properties of the polymer base
including homogeneity, viscosity, rate of set, solubility, heat
resistance, and others. Monomeric compounds are typically small
molecules having a molecular weight of less than about 1,000 having
from 1 to 4 carboxylic acid groups. Examples of such carboxylic
acid groups include C.sub.6-24 fatty acids such as lauric acid,
palmitic acid, oleic acid, stearic acid, linoleic acid, linolinic
acid, aracadonic acid, and others. Other examples include the
polyisobutylene and polypropylene substituted succinic acids, alkyl
substituted benzoic acids, alkyl substituted phthalic acids,
oxidized waxes, and others. Acid functional polymeric compounds
could also be used in the adhesives of the invention. Such
compositions include polymers having a molecular weight of about
500 and greater having an acid number of at least 75. Typical
examples of such acid containing polymers include polymers
containing repeating units of monomers such as acrylic acid,
methacrylic acid, maleic anhydride, maleic acid, fumaric acid,
vinyl benzoic acid, and other vinyl monomers containing at least
one carboxylic acid functional group or carboxylic acid generating
group such as an acid chloride or anhydride. Particular examples of
such polymers include polyacrylic acid, polymethacrylic acid,
ethylene acrylic acid copolymers, propylene methacrylic acid
copolymers, styrene maleic anhydride copolymers, carboxylated vinyl
acetate, carboxylated ethylene-styrene copolymers, carboxylated
ethylene vinyl acetate copolymers, and others well known to the
skilled chemist.
The sheet-like compositions of this invention can also contain a
hydroxy substituted organic compound. The hydroxy substituted
organic compound can be used to provide or enhance a number of
properties of the composition. The hydroxy composition in
combination with the other components of the invention can be used
to form uniform homogeneous single phase compositions. Further, the
hydroxy substituted organic compounds tend to produce polymeric
blends with workable viscosity, controllable rate of set and heat
resistance. If desired a sufficient quantity of a hydroxy
substituted organic compound can substantially reduce or enhance
pressure-sensitive adhesive (PSA) properties of the materials. For
example, liquid compounds tend to enhance PSA properties while
solids tend to reduce PSA properties. The hydroxy compositions can
be essentially aliphatic or aromatic, small molecule or polymeric.
Many hydroxy substituted organic compounds exist including
alcohols, hydroxy substituted waxes, polyalkylene oxide polymers
and copolymers such as CARBOWAX.RTM. and many others. Preferred
hydroxy substituted organic compounds include C.sub.10-30 fatty
acid alcohols, hydroxy substituted waxes, hydroxy substituted fatty
acid mono-, di- and triglycerides, hydroxy substituted fatty acids,
hydroxy substituted fats, hydroxy substituted fatty amides,
diacetin, polyalkylene oxide polymers and copolymers made from
polyethylene oxide, polypropylene oxide, and others. To ensure full
compatibility, we have found that the hydroxyl number of the
hydroxy substituted organic compound should be at least 150 and
preferably between 200 and 500, and that at a level of more 20 wt-%
or more of a 150 hydroxyl number hydroxy wax an effective amount, 5
to 10 wt-% of a C.sub.8-20 fatty acid, preferably a C.sub.8-20
saturated fatty acid can be used to ensure compatibility We believe
that the acid can be omitted if the hydroxyl number of the hydroxyl
compound is greater than 200.
Tackifying Agent or Resin
The polyoxazoline polymer itself can often have insufficient
pressure-sensitive adhesive (PSA) properties for certain treatment
purposes. The addition of a compatible tackifying resin is commonly
made to form a sufficiently adherent pressure-sensitive polymer
blend.
Many tackifying agents such as resins or resin blends are well
known in the art. Such resins include rosin acids, hydrogenated
rosins, tall oil pitch heads (residue), ACINTOL or UNITOL.RTM.
(Arizona Chemical), polyketones, polymerized mixed olefins, alkyl
resins, phenolic resins, and terpene-phenolic resins. Especially
preferred tackifying resins for use in the present compositions
include the rosin acids (SYLVATAX.RTM. , RX Silvachem Company), and
terpene-phenolic resins such as the NIREZ.RTM. series, e.g.
NIREZ.RTM. V-2040, V-2150 (Reichhold Chemicals, Inc., Pensacola,
Fla.), having a hydroxy number of at least about 150.
Suitable rosin acids, having the appropriate acid number, include
the FORAL.RTM. AX acidic resin available from Hercules Inc. This
resin is produced by hydrogenating wood rosin. Typical properties
include a softening point of 75.degree. C. by the Hercules drop
method, a refractive index of 1.4960 at 100.degree. C. and an
abietic acid value of 0.15% (uv). The product typically has an acid
number of about 150. Another preferred resin is the DYMEREX.RTM.
resin available from Hercules, Inc. This resin is composed
predominantly of dimer acids derived from rosin, and includes
lesser amounts of monomeric resin acids and neutral materials of
rosin origin. Typical properties include a softening point of
150.degree. C. by the Hercules drop method, a saponification number
of 145, an average molecular weight of about 502, a density of
about 1.069 kilograms per liter at 20.degree. C., 8% unsaponifiable
material, and an acid number of about 145. Another suitable
tackifying resin is the STAYBELITE.RTM. resin Hercules Inc.
Plasticizer
Plasticizers are generally classified as materials which can be
incorporated into another material to increase its workability,
flexibility, or distensibility. They can also enhance the
tackifying effect of the tackifying resin. The addition of a
plasticizer can lower melt viscosity, the temperature of the second
order transition point or the elastic modulus of the treated
material.
Commonly employed plasticizers include compounds of the following
classes: adipic acid derivatives, azeleic acid derivatives, benzoic
acid derivatives, diphenyl derivatives, citric acid derivatives,
epoxides, glycolates, isophthalic acid derivatives, maleic acid
derivatives, phosphorous acid derivatives, phthalic acid
derivatives, polyesters, trimelitates, and the like. Castor oil,
glyceryl trihydroxyoleate is available from a variety of chemical
suppliers including CasChem, Inc. of New Jersey. CasChem provides
this product as a variety of products having a Stokes viscosity of
7.5, specific gravity of 0.959, an iodine value of 86, a hydroxyl
value of 164, a saponification value of 180, and a pour point of
-10.degree. F.
Of the high acid plasticizers, especially suitable for use in the
invention are a liquid hydroxylated fatty acid or a conjugated
fatty acid, and isostearic acid. Isostearic acid is a commercially
available material. One supplier is Emery Industries, Inc., of
Cincinnati, Ohio. This product, sold under the mark EMERY 875-D,
generally has an acid value of between 191.0 and 201.0, a free
fatty acid value of 96-101%, a saponification value of 197-204, 3%
unsaponifiable, an iodine value of no greater than 3, and a Titer
of no greater than 9.0.degree. C.
Other plasticizers can be selected from any of the commercially
available benzoates, hydroxylated benzoates, or the acetates or
benzoates of polyols, such as the acetates or benzoates of C.sub.2
-C.sub.6 polyols comprising about 2-6 hydroxyl groups. Such
plasticizers include acetin, glycerol tribenzoate (BENZOFLEX.RTM.
S-404), or pentaerythritol tetrabenzoate (BENZOFLEX.RTM. S-552) or
the mixed dibenzoates of dipropylene glycol and diethylene glycol
(BENZOFLEX.RTM. 50, Velsicol Corp., Chicago, Ill.). Another useful
water insoluble plasticizer is butyl benzyl phthalate, available
from Monsanto Co. as SANTICIZER.RTM. 160.
Water soluble plasticizers are preferred for use in sheet-like
treatment compositions which are formulated so as to be water
releasable or soluble. Useful plasticizers of this type include the
liquid polyalkylene glycols, e.g. polyethylene glycols (PEG) of
molecular weights of about 200-800.
Wax
The hot melt adhesive compositions can also contain a wax. This
component can aid in viscosity control and can reduce the tendency
of the adhesive to block under conditions of high temperature,
pressure or high humidity. The wax preferably has an acid number
between about 50 and 300 or a hydroxy number of at least about 160.
If the wax is a high acid material, more preferably the acid number
will be between about 75 and 275, more preferably between about 85
and 200, or most preferably, between about 120 and 170. Lower acid
number waxes (acid No. 575 or OHNOB150) can be incompatible with
the polyalkyleneimine, and high acid number waxes can result in an
adhesive which corrodes hot melt equipment. We have found that
Hoechst "S" wax, a montan acid wax, is particularly suitable for
use in this invention, for reasons of compatibility, melt point,
viscosity control and rate of set. It is available from American
Hoechst Corporation of New Jersey. This material has a melting
point of from 80.degree.-83 .degree. C., a congealing point of
76.degree.-79.degree. C., an acid value of 140-155, and a
saponification value of 160-180. We have found that a hydroxyamide
wax (Paracin 220) with an OH No. of 300 can be used.
Copolymer
The formulation may contain an ethylene-acid copolymer, to provide
additional strength and toughness and increase the resistance to
cold. It will have the same acid number as specified previously in
connection with the wax component. A particularly suitable
ethylene-acid copolymer is the ELVAX.RTM. II ethylene copolymer
resin available from E. I. DuPont De Nemours & Co. This resin
is an ethylene acrylic acid copolymer. The grade 5950 is especially
suitable because of compatibility and toughness of the final film.
Typical properties of the ELVAX.RTM. II 5950 resin include an acid
number of 90, melt index (G/10min) of 25, tensile strength measured
at ASTM D 638-82 of 3,820 p.s.i., elongation, measured at ASTM D
638-82 of 480%, elastic (tensile) print modulus, ASTM D 638-82 of
25,000 p.s.i., flexural modulus, ASTM D 79--81, Meth. 1, Proc. A of
14,000 p.s.i., density at 23.degree. C. of 940 kg/m.sup.3,
durometer hardness, Shore A-2 of 94, and softening point, ring and
ball, 138.degree. C. Other suitable materials to provide the
increased strength, toughness, and resistance to cold flow include
temperature board failure.
Filler
The present adhesive formulations can also comprise an effective
amount of an inorganic extender or filler, such as calcium
carbonate, zinc oxide, alumina, clays, titanium dioxide, talc,
carbon black, and the like. For example, the film can be formulated
to be moisture-sensitive and/or water soluble can comprise up to
about 35 wt. % of a mineral extender which is preferably fatty
acid-ester coated to increase its organophilicity. One commercially
available filler of this type is the stearate-calcium carbonate
compound OMYACARB.RTM. UF-T (Omya, Inc., Proctor, Vt.). Another
commercially available filler is MINSPAR, a finely ground feldspar
available from Indusman.
The film compositions may also incorporate relatively small amounts
of adjuvants such as UV absorbers, heat stabilizers, release
agents, additional antiblocking agents and antioxidants. Typical
antioxidants include the IRGANOX.RTM. series (Ciba-Geigy) and the
distearyl pentaerythritol diphosphate (WESTON.RTM. 619, Borg-Warner
Chemicals). When present, such adjuvants will commonly make up less
than 5% by weight of the present adhesives.
Compatible polymers that can be included in the sheet-like
compositions of the invention include rubbery polymers and
copolymers, acid functional polymers having an acid number of at
least about 100, hydroxy (--OH) functional polymers having a
hydroxyl number of about 150 or greater, nitrilo functional
polymers including, for example, acrylonitrile, and other
compatible polymers. Such polymers include styrene acrylic acid
copolymers, ethylene acrylic acid copolymers, styrene alyl alcohol
copolymers, ethylene vinyl alcohol copolymers, ethylene
hydroxyethyl acrylate copolymers, ethylene hydroxyethyl
methacrylate copolymers, ethylene hydroxy propyl acrylate
copolymers, styrene-acrylonitrile copolymers,
styrene-butadiene-acrylonitrile copolymers, impact modified styrene
acrylonitrile rubbers, hydrogenated nitrile rubbers, nitrile rubber
wherein the nitrile polymer contains about 60 to 20 wt-%
acrylonitrile; polyvinyl pyrrolidone, polyvinyl caprolactan,
polyamides, made from piperazine or amine mixtures thereof;
halogenated polymers, epichlorohydrin rubber, chlorinated
polyolefin, vinyl chloride, vinyllidine chloride copolymers, and
others.
The following Examples further explain the manner of manufacture
and compositions of the treatment films of the invention and
include a best mode.
EXAMPLE I
Treatment Film Prepared From Hot Melt
Into a heated reaction vessel containing a blade mixer was placed
30 parts of a tackifying resin comprising a tall oil fatty acid
(FORAL AX), and 2 parts of a hindered phenolic antioxidant (IRGANOX
1076). The contents of the mixer were mixed and heated to a melt
temperature of about 250.degree. F. Into the melt was placed 30
parts of castor oil and 10 parts of feldspar filler. The material
in the mixer is agitated until uniform and into the mixer is placed
slowly 23 parts of a polyethyleneoxazoline polymer (500,000
molecular weight--PEOX). The contents of the mixer was agitated
after addition was complete until uniform and into the uniform
blend was added 5 parts of an ethylene acrylic acid copolymer
having an acid number of about 80. The contents were agitated until
uniform and the uniform blend was cast into a uniform layer having
a thickness of about 5 mils. The layer was nontacky and had
substantial cohesive strength.
EXAMPLE II
Structural Layer
Into a stainless steel reaction vessel heated to
350.degree.-375.degree. F. having a blade mixer was placed 25 parts
of a tackifying resin (PICCOFYN T-125), 20 parts of castor oil. The
components were mixed in the vessel under conditions of high shear
until homogeneous for approximately 10 minutes. To the mixture was
added 10 parts of a hydroxy wax (PARICIN 220) and 18 parts of
feldspar (MINSPAR No. 7). The mixture was agitated under high shear
until uniform at 350.degree.-375.degree. F. for 10 minutes. Into
the uniform, homogeneous blend was slowly added 25 parts of a
polyethyloxazoline polymer having a molecular weight of 500,000
(PEOX--500). During the step-wise addition, the mixture was
agitated at high shear and after the addition was complete (15
minutes) the composition was agitated until homogeneous. To the
homogeneous melt was added 2 parts of butyl zymate antioxidant. The
material was capable of being extruded at elevated temperature,
approximately 350.degree.-375.degree. F. into thin, 0.1-10 mil
structural nontacky sheets.
EXAMPLE III
Pressure Sensitive Adhesive
In a heated stainless steel reaction vessel at 400.degree. F.,
equipped with a stainless steel blade was added 66.8 grams of a
tackifying resin (FORAL AX), 61.8 grams of castor oil, 3.4 grams of
butyl zymate antioxidant. The blend was mixed at high shear for 20
minutes until homogeneous. Into the uniform melt was slowly added
44 grams of polyethyloxazoline polymer (PEOX--500,000 molecular
weight). The melt was mixed at high shear until homogenous
(approximately 120 minutes). Into the melt was slowly added 22.8
grams of a styrene-butadiene-styrene block copolymer (KRATON 1102)
and the melt was mixed until homogeneous (about 40 minutes). Once
uniform, 0.88 gram of a 1% aqueous acetic acid solution containing
0.4% of chitosan was slowly added to the melt. Mixing was
maintained until uniform and into the uniform melt was added 0.32
gram of a tincture of iodine containing 2 wt. % iodine in a 47
volume-% aqueous alcohol solution.
EXAMPLE IV
PSA Layer
Example III was repeated except that 13 parts of a
styrene-isoprene-styrene block copolymer (KRATON 1117) was
substituted for the 13 parts of KRATON 1102.
EXAMPLE V
Example III was repeated except that the 35 parts of castor oil was
omitted and 35 parts of an ethylene acrylic acid polymer having an
acid number of 120 (AC-5120) was substituted for the castor
oil.
EXAMPLE II AND VI-XII
The following Examples of Table 2 are prepared following the
blending procedures shown in the above Examples. The table lists
the properties of materials made for the invention using the
polyethyloxazoline polymer and a variety of functional compounds in
useful blends.
TABLE 2
__________________________________________________________________________
Ingredient II VI VII VIII IX X XI XII
__________________________________________________________________________
PeOx (500,000 MW) 23.0 25.0 25.0 23.0 30.0 10.0 25.0 20.0 Rosin
acid 30.0 38.0 33.0 30.0 30.0 50.0 40.0 Antioxidant 2.0 2.0 2.0 2.0
2.0 2.0 2.0 Castor oil 30.0 35.0 35.0 35.0 30.0 38.0 20.0 Feldspar
(filler) 10.0 18.0 EAC* (Acid No. = 80) 5.0 5.0 EAC* (Acid No. =
120) 10.0 Dimer acid 8.0 Phenol-modified terpene resin 25.0
Hydroxystearamide wax 10.0 Isostearic acid 30.0 Ethylene-acrylic
acid 10.0 interpolymer (Acid No. = 90) 180.degree. Peel
(initial)/ln. in. 3.5 lbs. 3.5 lbs. 3.5 lbs. 3.5 lbs. 2.2 lbs. 2.2
lbs. (24 hrs.)/ln. in. 6.5 lbs. 5.5 lbs. 5.5 lbs. 4.5 lbs. Static
Shear 200 min. 100 min. 150 min. 160 min. 40 min. Loop tack 26 oz.
30 oz. 30 oz. 24 oz. 18 oz. Polyken tack 425 650 400 550 458 g
Viscosity, 300.degree. F. (cPs) 8750 4500 6000 3250
__________________________________________________________________________
*EAC = ethyleneacrylic acid copolymer.
EXAMPLE XIII
200 grams of the material of Example III was dissolved in an
aqueous ammoniacal (pH 10) solution containing 20 grams of an
acetylenic glycol surfactant blend in polypropylene glycol
(SURFYNOL TG-E) in 250 grams of water. The material was mixed at
180.degree. F. until a uniform suspension solution was formed. The
solution (about 50 wt. % solids was sprayed on the skin surface
resulting in an intact, tacky treatment film.
The Examples shown above in conjunction with data relating to the
properties of the treatment film clearly demonstrates the utility
of the films of this invention for the purpose of treating skin. It
is apparent that the material can be made in a variety of formats,
can be applied to the surface of the skin, and can have useful
treatment properties.
The discussion, Examples and data found above provide a complete
explanation of the current understanding of the invention. However,
since many embodiments of the invention may be derived without
department from the spirit and scope of the invention, the
invention resides in the claims hereinafter appended.
* * * * *